PROJECT SUMMARY The objective of this Phase II SBIR is to test the safety and efficacy of an osteoinductive lumbar spinal fusion implant in an ovine model. In preliminary work, lower impedance piezoelectric materials that generate power for direct current (DC) electrical stimulation applications were manufactured and electromechanically characterized. In an osteoinductive spinal fusion implant design, an insulated piezoelectric composite acts as a power generator to supply negative DC electrical stimulation to a Titanium electrode that is mounted on the surface of the implant. In the Phase I STTR research, a more cost-effective and mechanically sound method of manufacturing the piezoelectric lumbar spinal fusion implant was developed using easy to use epoxy materials. Evoke Medical has formed strategic partnerships that will allow us to will design, build, and test PEEK-based piezoelectric interbody implants that can be manufactured in volume at a reasonable cost. In lumbar spine fusion, the success rate reported in published studies ranges from approximately 50-90%. This disparity is primarily due to the high number of difficult-to-fuse patients (e.g., smokers, diabetics). DC electrical stimulation has been shown to help increase success rates in the difficult-to-fuse population and accelerate the rate of bone healing in all patients. Preliminary large animal studies using an encapsulated piezoelectric composite spinal fusion implant showed that it could generate faster and better healing in spine fusion. While preliminary studies show great promise, the concept must be proven with PEEK-based implants and tested with sufficient numbers of animals to show statistical differences. The premise of the Phase II proposal is that an interbody implant with integrated DC stimulation will promote a faster and more robust spinal fusion in comparison to the current standard of care in a large animal model. With the cost-effective manufacturing methods and demonstration of safety and efficacy in Phase II, Evoke Medical can then move forward with commercialization of this potentially disruptive technology that may eventually increase success rates of spinal fusion in the difficult to fuse populations. In Specific Aim 1, we will implement the cost-effective methods of manufacturing stacked layered PEEK-based piezoelectric composite TLIF implants that were developed in the Phase I work. In Specific Aim 2, we will prove that the PEEK-based piezoelectric TLIF implants can meet or exceed mechanical requirements of a legally marketed TLIF predicate device using recommended ASTM standards for interbody testing while maintaining the ability to produce sufficient power for bone healing. In Specific Aim 3, we will demonstrate safety and efficacy of the piezoelectric TLIF implant in an ovine model. The results of this work will set the stage for Phase III funding of early clinical trials required for regulatory clearance and subsequent acquisition by a large medical device company. The thoracolumbar spine interbody market is over $1.3B/year with a compound annual growth rate of 5.6%. The proposed device is hypothesized to increase the success of healing and decrease the time to heal, thus decreasing overall cost of care and human suffering.